Manufacture of springs



Nov. 13, 1928.

J. M. 'SGHOONMAKER, JR, ET AL MANUFACTURE OF SPRINGS Filed May 1925 4Sheets-Sheet 1 EOOO WITNESSES d ETAL Nov. 13, l928.

J. M. SCHOONMAKER, JR.

MANUFACTURE OF SPRINGS 4 Sheets-Sheet 2 Filed May a, 1925 Fl 5. Z

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J. M. SCHOONMAKER, JR., ET AL MANUFACTURE OF SPRINGS Filed 1925 4Sheets-Sheet 3 w W/ nvsses W 771'.

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J. M. SCHOONMAKER, JR, ET AL MANUFACTURE OF SPRINGS Filed May 6, 1925 4Sheets-Sheet 4 Patented Nov. 13, 1928.

UNITED STATES PATENT'OFFICE.

JAMES'M. SCHOONMAKER, JR., OF SEWIGKLEY, AND DONALD T. GLEASON, OF CORA-OPOLIS, PENNSYLVANIA, ASSIGNORS 'lO STANDARD STEEL SPRING COMPANY, A

CORPORATION OF PENNSYLVANIA.

MANUFACTURE OF SPRINGS.

Application filed May 6,

This invention relates to the manufacture of springs and moreparticularly to a method and apparatus for bending the main plates ofleaf springs.

Although a method of and apparatus for bending spring blanks by coldrolling are disclosed and claimed in Patents No. 1,375,038, of April 19,1921, and No. 1,381,014, of June 7, 1921, both granted upon applicationsof Theodore dOrville, the bending of the eye plates of leaf springs byrolling has been diflicult to accomplish because of the presence of thespring eye at each end of'the blank. If plain surface bending rolls wereto be used the spring eye at each end of the blank would be crushed outof shape.

An object of this invention is to provide a method of rolling the eyeplates of leaf springs after the spring eyes have been formed thereon. I

A further object is to provide a machine for cheaply and effectivelyforming the eye plates of leaf springs by rolling.

A still further object is to provide a ma chine of the type setforthwhich is adapted to roll the eye plates of springs of any size withoutrequiring any change in or adjustment of the machine, except adjustmentof the top roll when it is desired to change the camber.

A still further object is to provide a bending. roll which is adapted tobe substituted for an ordinary bending roll in a well-known type ofspring leaf bending machine as to adapt such a machine to the rolling ofeye plates. 7

These and other objects which will be apparent to those skilled in thisparticular art may be accomplished byv means of a machine such as isillustrated, for example. in the ac companying drawings, in which Figure1 is a side elevation of a machine constructed in accordanc with oneembodiment of this invention. Fig. 2 is a similar view of certain of theelements of Fig. 1, taken on an enlarged scale from the rear of themachine illustrated in Fig. 1. Fig. 3 is a vertical transverse sectionon the line 3-3 of Fig. 2 and Figs. 1 to 8 are diagrammatic viewsillustrating various steps which constitute the improved method ofrolling'the main plates of leaf springs;

In carrying out this inventon there is preferably provided a set ofthree triangularly arranged bending rolls. The two lower rolls 1925.Serial No. 23,396

are the driving rolls and preferably have their axes positioned in thesame horizontal plane and parallel to each other. The third bending rollis of somewhat larger diameter and has its axis positioned above and ina vertlcal plane midway between theraxes of the two. lower rolls. Theupper roll is driven by engagement with the work.

Prior to bending, the blank for the main plate of a leaf spring has itsends bent to form spring eyes. The upper roll is provided with aconcavity for accommodating the enlarged end of rthe spring blankformed'by the eye. The blank is passed into the rolls and the eye'on'the forward end is received within the concavity'of the upper roll. Ifthe blank were then passed directly through the rolls it would benecessary to have the upper roll of circumference equal to the distancebetween the spring eyes so that. the eye.

attherear of the blank would coincide with the eye accommodatingconcavity in the roll surface, as it passes through the rolls, toprevent the eye from being rolled out of shape. This would necessitatea: different sized roll for each length of spring. In order to overcomethis difficulty and provide a method of rolling the eye plates of leafsprings regardless of their length and without changing or requiringdifferent forms of rolls, other than adjustment of the upper roll tovary the camber of the finished plate, we proceed as. follows:

After the blank has been partially passed through the rolls and has hada part only of its length bent to form, it isreleased from the rollingpressure. This is due, in the present instance, to the fact that the cutaway portion of the roll surface is moved to the point where the blankis subjected to the bite of the rolls. The upper roll being of reduceddiameter at that point, the blank is released from the pressure of theroll. While free of this pressure the blank is drawn back through the Arolls until the spring eyeat the rear of the blank is positioned adistance from the bite of the upper roll exactly equal to thecircumference thereof and the roll itself is po sitioned so that theedge of the eye accommodating cavity in theroll surface is at the pointwhere the blank is first subjected to the rolling pressure. or, in otherwords, the cavity is positioned at the point where the blank is firstsubjected to the bite of the rolls. The Y blank is then passed onthrough the rolls and the spring eye at the rear of the blank passesthrough the rolls coincidently with the rotation of the eyeaccommodating cavity, because of the fact that it has been positioned adistance from the rolls equal to the circumference of the upper roll sothat one complete rotation of this roll serves to complete the rollingof the blank and the cavity therein meets the eye at the rear of theblank so as to accommodate it as it asses throtwh the rolls b andprevent the distortion thereof.

The preferred form of appara bus for carrying out this method isillustrated in Figs. 1 to 3, and'is constructed substantially inaccordance with the machine disclosed and claimed in the above notedpatents; together with certain modifications and improvements foradaptingthe machine to the rolling of eye plates for leaf springs inaccordance with my improved method. i I

The machine provides with two horizontally aligned, parallel drivenrolls 10 and 11 which are driven by the mechanism described in the saidpatent.

An upper bending roll 12 is mounted on a shaft 13 disposed above andmidway between the axes of the two lower rolls. The shaft 13 runs inroller bearings 1d mounted in a vertically adiustable housing 15 asdescribed in the said patent. i As illustrated,'the upper bending roll12 is provided with a flat surface 16, and a curved shoulder 17. c v Ahandwheel 18 is secured to one end of the shaft 13 and is positionedoutside of the housing 15. In order to prevent dirt'from entering thebearing 14: adjacent the hand wheel its inner face 19 is provided with acircular groove 20 adapted to receive a circular flange 21 formed on thehousing, thus providing an interleaving seal, see Fig. 3. The hub 22 ofthe hand whe l is surrounded by a brake 23 having one end secured to a.post 24 eX- tending horizontally outward from thehousing 15'. The otherend of the brake band is connected to a rod 25 passing through aperforation 26 formed in the post 24. A nut 27 is threaded to the upperend of the rod 25 and a helical spring 28 is compressed between the nutand a washer 29 which seats against the side of the post 24. A wing nut30 may be provided for locking the spring adpisting nut 27 in position.

A gauge or marker 83 is mounted on the frame of the machine at distancefrom the center line of the back bottom 'roll exactly equal to thecircumference of the upper bear ing roll.

In operation the upper roll is rotated by means of the hand wheel untilthe flat fate e16 thereof is opposite the lower cooperating bendingrolls10 and 11. The spring eye at the forward end o the blank is theninserted between the rolls as shown in Fig.- 4. Rolling ing the rollingthereof.

is commenced and the upper roll is started by means of the hand wheel.As soon as the c of the shoulder 17 engages the nl; the roll itself isrotated by frici form by its pas- 1. More the blank has t r gh therolls, however, t surface 16 again comes opposite the loner rolls so asto relieve the blank of the 11 'ngpressure and free the upper roll fromoi remcnt with t is blank. The spring p Weed brake band 23 serves tostop the rotation of the upper bending roll before the shoulder 17 can again engage the blank. At this time the blank is, of course, free of thebite of the rolls and it moved back until its end is opposite the marker33 as shown in Fig. (3. he latter is positioned a distance from thecenter line of the back bottom roll, or from the point of the first biteof the rolls, just equal to the 'circun'iference of the top roll. Thelatter is then rotated by the hand wheel until its circular surfaceagain engages the ik when it will again be driven by friction and therolling of the blank completed. Due to the fact that the spring eye atthe rear of the blank has heel positioned a distance from thezbite o ther lls which is exactly equal to the circumference o the top roll theflattened surface 16 meets the spring eye at the rear of the blank asthe latter enters the rolls so that it passcs throughwithout distortionas indicated in Fig. 8.

fv hat we claim as new and desire to secure by Letters Patent is:

1. The method of bending which consists in passing a blank betweenrolls, releasing said blank from the pressure of said rolls, positioningthe end of said blank a predetermined distance from said rolls andcompleting the rollingthereof.

2. The method of bending which consists in starting a blank through asetof rolls to impart a camber thereto, releasing said blank from thepressure of said rolls, drawing said blank back a predetermined distanceand completing the rolling thereof.

8. The methodof bending which consists in passing a blank between rollsv rolling a section of said blank to'impart a camber thereto releasingsaid blank from the pressure of saidrolls, moving said blanklongitudinallv apredetermined distance and completing the rollingthereof.

l. lhe method of bending which consists in passing a blank between rollsso as to bend a section of said blank, releasing said blank from thepressure of said rolls, positioning the unrolled end of said blank apredetermined distance from said rolls and complet- 5. The method obending a leaf spring blank while cold which consists in passing a blankbetween rolls so as to bend a section of said blank, releasing saidblank from the cavity for accommodating the spring eyes formed at eachend of the blank and means permittin the adjustment of said blank duning rolling so that said concavity receives the eye at the rear of eachblank as it passes through said rolls 7 7 A bending machine for the eyeplates of leaf springs including in combination, a bending roll havingan irregularity in the surface thereof for accommodating the springeyes, said surface being formed so as to release theblank from contactWith said roll after partial rolling thereof and means for gauging theposition of said blank so thatits unfinished end is located. a distancefrom the bite of said roll equal to the circumference of said roll.

8. A bending machine for spring leaves including in combination, bendingrolls, one of said rolls having a surface formed so as to release ablank from rolling pressure to permit a longitudinal movement thereofafter partial rolling and a gauge for determining the extent of thelongitudinal movement of the blank.

9. A bending machine for the eye plates of leaf springs including incombination, a

bending roll having an irregularity in the surface thereof foraccommodating the spring eyes, said surface being formed so as torelease the blank from contact With said roll after partial rolling andmeans for stopping said roll when said blank is so released.

10. A bending machine for the eye plates of leaf springs including incombination, a bending roll having an irregularity in the surfacethereof for accommodating the spring eyes, said surface being formed soas to re lease the blank from contact with said roll to 1 ermitlongitudinal movement of said blank after partial rolling, means forstop ping said roll when said blank is so released and means forstarting said roll so as to com plete the bending of said blank.

11. A bending machine for the eye plates of leaf springs including incombination, a bending roll having an irregularity in the surfacethereof for accommodating the spring eyes, said surface being formedsoas to release the blank from contact with said roll after partialrolling, a brake for stopping said roll when said blank is so released,means for gauging the position of said blank so that its unfinished endis located a predetermined distance from the bite of said roll and ahand Wheel for starting said roll so as to complete the bending of saidblank.

In testimony whereof, We have hereunto set our names this 28 day ofApril, 1925.

JAMES M. SGHOONMAKER, JR. DONALD T. GLEASON.

